/* Pretty handling of time axes.

Copyright (c) 2007-2014 IOLA and Ole Laursen.
Licensed under the MIT license.

Set axis.mode to "time" to enable. See the section "Time series data" in
API.txt for details.
*/

(function ($) {
  'use strict';

  var options = {
    xaxis: {
      timezone: null, // "browser" for local to the client or timezone for timezone-js
      timeformat: null, // format string to use
      twelveHourClock: false, // 12 or 24 time in time mode
      monthNames: null, // list of names of months
      timeBase: 'seconds' // are the values in given in mircoseconds, milliseconds or seconds
    },
    yaxis: {
      timeBase: 'seconds'
    }
  };

  var floorInBase = $.plot.saturated.floorInBase;

  // Method to provide microsecond support to Date like classes.
  var CreateMicroSecondDate = function (DateType, microEpoch) {
    var newDate = new DateType(microEpoch);

    var oldSetTime = newDate.setTime.bind(newDate);
    newDate.update = function (microEpoch) {
      oldSetTime(microEpoch);

      // Round epoch to 3 decimal accuracy
      microEpoch = Math.round(microEpoch * 1000) / 1000;

      // Microseconds are stored as integers
      this.microseconds = 1000 * (microEpoch - Math.floor(microEpoch));
    };

    var oldGetTime = newDate.getTime.bind(newDate);
    newDate.getTime = function () {
      var microEpoch = oldGetTime() + this.microseconds / 1000;
      return microEpoch;
    };

    newDate.setTime = function (microEpoch) {
      this.update(microEpoch);
    };

    newDate.getMicroseconds = function () {
      return this.microseconds;
    };

    newDate.setMicroseconds = function (microseconds) {
      var epochWithoutMicroseconds = oldGetTime();
      var newEpoch = epochWithoutMicroseconds + microseconds / 1000;
      this.update(newEpoch);
    };

    newDate.setUTCMicroseconds = function (microseconds) {
      this.setMicroseconds(microseconds);
    }

    newDate.getUTCMicroseconds = function () {
      return this.getMicroseconds();
    }

    newDate.microseconds = null;
    newDate.microEpoch = null;
    newDate.update(microEpoch);
    return newDate;
  }

  // Returns a string with the date d formatted according to fmt.
  // A subset of the Open Group's strftime format is supported.

  function formatDate(d, fmt, monthNames, dayNames) {
    if (typeof d.strftime === "function") {
      return d.strftime(fmt);
    }

    var leftPad = function (n, pad) {
      n = "" + n;
      pad = "" + (pad == null ? "0" : pad);
      return n.length === 1 ? pad + n : n;
    };

    var formatSubSeconds = function (milliseconds, microseconds, numberDecimalPlaces) {
      var totalMicroseconds = milliseconds * 1000 + microseconds;
      var formattedString;
      if (numberDecimalPlaces < 6 && numberDecimalPlaces > 0) {
        var magnitude = parseFloat('1e' + (numberDecimalPlaces - 6));
        totalMicroseconds = Math.round(Math.round(totalMicroseconds * magnitude) / magnitude);
        formattedString = ('00000' + totalMicroseconds).slice(-6, -(6 - numberDecimalPlaces));
      } else {
        totalMicroseconds = Math.round(totalMicroseconds)
        formattedString = ('00000' + totalMicroseconds).slice(-6);
      }
      return formattedString;
    };

    var r = [];
    var escape = false;
    var hours = d.getHours();
    var isAM = hours < 12;

    if (!monthNames) {
      monthNames = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"];
    }

    if (!dayNames) {
      dayNames = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"];
    }

    var hours12;
    if (hours > 12) {
      hours12 = hours - 12;
    } else if (hours === 0) {
      hours12 = 12;
    } else {
      hours12 = hours;
    }

    var decimals = -1;
    for (var i = 0; i < fmt.length; ++i) {
      var c = fmt.charAt(i);

      if (!isNaN(Number(c)) && Number(c) > 0) {
        decimals = Number(c);
      } else if (escape) {
        switch (c) {
          case 'a':
            c = "" + dayNames[d.getDay()];
            break;
          case 'b':
            c = "" + monthNames[d.getMonth()];
            break;
          case 'd':
            c = leftPad(d.getDate());
            break;
          case 'e':
            c = leftPad(d.getDate(), " ");
            break;
          case 'h': // For back-compat with 0.7; remove in 1.0
          case 'H':
            c = leftPad(hours);
            break;
          case 'I':
            c = leftPad(hours12);
            break;
          case 'l':
            c = leftPad(hours12, " ");
            break;
          case 'm':
            c = leftPad(d.getMonth() + 1);
            break;
          case 'M':
            c = leftPad(d.getMinutes());
            break;
          // quarters not in Open Group's strftime specification
          case 'q':
            c = "" + (Math.floor(d.getMonth() / 3) + 1);
            break;
          case 'S':
            c = leftPad(d.getSeconds());
            break;
          case 's':
            c = "" + formatSubSeconds(d.getMilliseconds(), d.getMicroseconds(), decimals);
            break;
          case 'y':
            c = leftPad(d.getFullYear() % 100);
            break;
          case 'Y':
            c = "" + d.getFullYear();
            break;
          case 'p':
            c = (isAM) ? ("" + "am") : ("" + "pm");
            break;
          case 'P':
            c = (isAM) ? ("" + "AM") : ("" + "PM");
            break;
          case 'w':
            c = "" + d.getDay();
            break;
        }
        r.push(c);
        escape = false;
      } else {
        if (c === "%") {
          escape = true;
        } else {
          r.push(c);
        }
      }
    }

    return r.join("");
  }

  // To have a consistent view of time-based data independent of which time
  // zone the client happens to be in we need a date-like object independent
  // of time zones.  This is done through a wrapper that only calls the UTC
  // versions of the accessor methods.

  function makeUtcWrapper(d) {
    function addProxyMethod(sourceObj, sourceMethod, targetObj, targetMethod) {
      sourceObj[sourceMethod] = function () {
        return targetObj[targetMethod].apply(targetObj, arguments);
      };
    }

    var utc = {
      date: d
    };

    // support strftime, if found
    if (d.strftime !== undefined) {
      addProxyMethod(utc, "strftime", d, "strftime");
    }

    addProxyMethod(utc, "getTime", d, "getTime");
    addProxyMethod(utc, "setTime", d, "setTime");

    var props = ["Date", "Day", "FullYear", "Hours", "Minutes", "Month", "Seconds", "Milliseconds", "Microseconds"];

    for (var p = 0; p < props.length; p++) {
      addProxyMethod(utc, "get" + props[p], d, "getUTC" + props[p]);
      addProxyMethod(utc, "set" + props[p], d, "setUTC" + props[p]);
    }

    return utc;
  }

  // select time zone strategy.  This returns a date-like object tied to the
  // desired timezone
  function dateGenerator(ts, opts) {
    var maxDateValue = 8640000000000000;

    if (opts && opts.timeBase === 'seconds') {
      ts *= 1000;
    } else if (opts.timeBase === 'microseconds') {
      ts /= 1000;
    }

    if (ts > maxDateValue) {
      ts = maxDateValue;
    } else if (ts < -maxDateValue) {
      ts = -maxDateValue;
    }

    if (opts.timezone === "browser") {
      return CreateMicroSecondDate(Date, ts);
    } else if (!opts.timezone || opts.timezone === "utc") {
      return makeUtcWrapper(CreateMicroSecondDate(Date, ts));
    } else if (typeof timezoneJS !== "undefined" && typeof timezoneJS.Date !== "undefined") {
      var d = CreateMicroSecondDate(timezoneJS.Date, ts);
      // timezone-js is fickle, so be sure to set the time zone before
      // setting the time.
      d.setTimezone(opts.timezone);
      d.setTime(ts);
      return d;
    } else {
      return makeUtcWrapper(CreateMicroSecondDate(Date, ts));
    }
  }

  // map of app. size of time units in seconds
  var timeUnitSizeSeconds = {
    "microsecond": 0.000001,
    "millisecond": 0.001,
    "second": 1,
    "minute": 60,
    "hour": 60 * 60,
    "day": 24 * 60 * 60,
    "month": 30 * 24 * 60 * 60,
    "quarter": 3 * 30 * 24 * 60 * 60,
    "year": 365.2425 * 24 * 60 * 60
  };

  // map of app. size of time units in milliseconds
  var timeUnitSizeMilliseconds = {
    "microsecond": 0.001,
    "millisecond": 1,
    "second": 1000,
    "minute": 60 * 1000,
    "hour": 60 * 60 * 1000,
    "day": 24 * 60 * 60 * 1000,
    "month": 30 * 24 * 60 * 60 * 1000,
    "quarter": 3 * 30 * 24 * 60 * 60 * 1000,
    "year": 365.2425 * 24 * 60 * 60 * 1000
  };

  // map of app. size of time units in microseconds
  var timeUnitSizeMicroseconds = {
    "microsecond": 1,
    "millisecond": 1000,
    "second": 1000000,
    "minute": 60 * 1000000,
    "hour": 60 * 60 * 1000000,
    "day": 24 * 60 * 60 * 1000000,
    "month": 30 * 24 * 60 * 60 * 1000000,
    "quarter": 3 * 30 * 24 * 60 * 60 * 1000000,
    "year": 365.2425 * 24 * 60 * 60 * 1000000
  };

  // the allowed tick sizes, after 1 year we use
  // an integer algorithm

  var baseSpec = [
    [1, "microsecond"], [2, "microsecond"], [5, "microsecond"], [10, "microsecond"],
    [25, "microsecond"], [50, "microsecond"], [100, "microsecond"], [250, "microsecond"], [500, "microsecond"],
    [1, "millisecond"], [2, "millisecond"], [5, "millisecond"], [10, "millisecond"],
    [25, "millisecond"], [50, "millisecond"], [100, "millisecond"], [250, "millisecond"], [500, "millisecond"],
    [1, "second"], [2, "second"], [5, "second"], [10, "second"],
    [30, "second"],
    [1, "minute"], [2, "minute"], [5, "minute"], [10, "minute"],
    [30, "minute"],
    [1, "hour"], [2, "hour"], [4, "hour"],
    [8, "hour"], [12, "hour"],
    [1, "day"], [2, "day"], [3, "day"],
    [0.25, "month"], [0.5, "month"], [1, "month"],
    [2, "month"]
  ];

  // we don't know which variant(s) we'll need yet, but generating both is
  // cheap

  var specMonths = baseSpec.concat([[3, "month"], [6, "month"],
    [1, "year"]]);
  var specQuarters = baseSpec.concat([[1, "quarter"], [2, "quarter"],
    [1, "year"]]);

  function dateTickGenerator(axis) {
    var opts = axis.options,
      ticks = [],
      d = dateGenerator(axis.min, opts),
      minSize = 0;

    // make quarter use a possibility if quarters are
    // mentioned in either of these options
    var spec = (opts.tickSize && opts.tickSize[1] ===
      "quarter") ||
    (opts.minTickSize && opts.minTickSize[1] ===
      "quarter") ? specQuarters : specMonths;

    var timeUnitSize;
    if (opts.timeBase === 'seconds') {
      timeUnitSize = timeUnitSizeSeconds;
    } else if (opts.timeBase === 'microseconds') {
      timeUnitSize = timeUnitSizeMicroseconds;
    } else {
      timeUnitSize = timeUnitSizeMilliseconds;
    }

    if (opts.minTickSize !== null && opts.minTickSize !== undefined) {
      if (typeof opts.tickSize === "number") {
        minSize = opts.tickSize;
      } else {
        minSize = opts.minTickSize[0] * timeUnitSize[opts.minTickSize[1]];
      }
    }

    for (var i = 0; i < spec.length - 1; ++i) {
      if (axis.delta < (spec[i][0] * timeUnitSize[spec[i][1]] +
        spec[i + 1][0] * timeUnitSize[spec[i + 1][1]]) / 2 &&
        spec[i][0] * timeUnitSize[spec[i][1]] >= minSize) {
        break;
      }
    }

    var size = spec[i][0];
    var unit = spec[i][1];
    // special-case the possibility of several years
    if (unit === "year") {
      // if given a minTickSize in years, just use it,
      // ensuring that it's an integer

      if (opts.minTickSize !== null && opts.minTickSize !== undefined && opts.minTickSize[1] === "year") {
        size = Math.floor(opts.minTickSize[0]);
      } else {
        var magn = parseFloat('1e' + Math.floor(Math.log(axis.delta / timeUnitSize.year) / Math.LN10));
        var norm = (axis.delta / timeUnitSize.year) / magn;

        if (norm < 1.5) {
          size = 1;
        } else if (norm < 3) {
          size = 2;
        } else if (norm < 7.5) {
          size = 5;
        } else {
          size = 10;
        }

        size *= magn;
      }

      // minimum size for years is 1

      if (size < 1) {
        size = 1;
      }
    }

    axis.tickSize = opts.tickSize || [size, unit];
    var tickSize = axis.tickSize[0];
    unit = axis.tickSize[1];

    var step = tickSize * timeUnitSize[unit];

    if (unit === "microsecond") {
      d.setMicroseconds(floorInBase(d.getMicroseconds(), tickSize));
    } else if (unit === "millisecond") {
      d.setMilliseconds(floorInBase(d.getMilliseconds(), tickSize));
    } else if (unit === "second") {
      d.setSeconds(floorInBase(d.getSeconds(), tickSize));
    } else if (unit === "minute") {
      d.setMinutes(floorInBase(d.getMinutes(), tickSize));
    } else if (unit === "hour") {
      d.setHours(floorInBase(d.getHours(), tickSize));
    } else if (unit === "month") {
      d.setMonth(floorInBase(d.getMonth(), tickSize));
    } else if (unit === "quarter") {
      d.setMonth(3 * floorInBase(d.getMonth() / 3,
        tickSize));
    } else if (unit === "year") {
      d.setFullYear(floorInBase(d.getFullYear(), tickSize));
    }

    // reset smaller components

    if (step >= timeUnitSize.millisecond) {
      if (step >= timeUnitSize.second) {
        d.setMicroseconds(0);
      } else {
        d.setMicroseconds(d.getMilliseconds() * 1000);
      }
    }
    if (step >= timeUnitSize.minute) {
      d.setSeconds(0);
    }
    if (step >= timeUnitSize.hour) {
      d.setMinutes(0);
    }
    if (step >= timeUnitSize.day) {
      d.setHours(0);
    }
    if (step >= timeUnitSize.day * 4) {
      d.setDate(1);
    }
    if (step >= timeUnitSize.month * 2) {
      d.setMonth(floorInBase(d.getMonth(), 3));
    }
    if (step >= timeUnitSize.quarter * 2) {
      d.setMonth(floorInBase(d.getMonth(), 6));
    }
    if (step >= timeUnitSize.year) {
      d.setMonth(0);
    }

    var carry = 0;
    var v = Number.NaN;
    var v1000;
    var prev;
    do {
      prev = v;
      v1000 = d.getTime();
      if (opts && opts.timeBase === 'seconds') {
        v = v1000 / 1000;
      } else if (opts && opts.timeBase === 'microseconds') {
        v = v1000 * 1000;
      } else {
        v = v1000;
      }

      ticks.push(v);

      if (unit === "month" || unit === "quarter") {
        if (tickSize < 1) {
          // a bit complicated - we'll divide the
          // month/quarter up but we need to take
          // care of fractions so we don't end up in
          // the middle of a day
          d.setDate(1);
          var start = d.getTime();
          d.setMonth(d.getMonth() +
            (unit === "quarter" ? 3 : 1));
          var end = d.getTime();
          d.setTime((v + carry * timeUnitSize.hour + (end - start) * tickSize));
          carry = d.getHours();
          d.setHours(0);
        } else {
          d.setMonth(d.getMonth() +
            tickSize * (unit === "quarter" ? 3 : 1));
        }
      } else if (unit === "year") {
        d.setFullYear(d.getFullYear() + tickSize);
      } else {
        if (opts.timeBase === 'seconds') {
          d.setTime((v + step) * 1000);
        } else if (opts.timeBase === 'microseconds') {
          d.setTime((v + step) / 1000);
        } else {
          d.setTime(v + step);
        }
      }
    } while (v < axis.max && v !== prev);

    return ticks;
  };

  function init(plot) {
    plot.hooks.processOptions.push(function (plot) {
      $.each(plot.getAxes(), function (axisName, axis) {
        var opts = axis.options;
        if (opts.mode === "time") {
          axis.tickGenerator = dateTickGenerator;

          // if a tick formatter is already provided do not overwrite it
          if ('tickFormatter' in opts && typeof opts.tickFormatter === 'function') return;

          axis.tickFormatter = function (v, axis) {
            var d = dateGenerator(v, axis.options);

            // first check global format
            if (opts.timeformat != null) {
              return formatDate(d, opts.timeformat, opts.monthNames, opts.dayNames);
            }

            // possibly use quarters if quarters are mentioned in
            // any of these places
            var useQuarters = (axis.options.tickSize &&
              axis.options.tickSize[1] === "quarter") ||
              (axis.options.minTickSize &&
                axis.options.minTickSize[1] === "quarter");

            var timeUnitSize;
            if (opts.timeBase === 'seconds') {
              timeUnitSize = timeUnitSizeSeconds;
            } else if (opts.timeBase === 'microseconds') {
              timeUnitSize = timeUnitSizeMicroseconds;
            } else {
              timeUnitSize = timeUnitSizeMilliseconds;
            }

            var t = axis.tickSize[0] * timeUnitSize[axis.tickSize[1]];
            var span = axis.max - axis.min;
            var suffix = (opts.twelveHourClock) ? " %p" : "";
            var hourCode = (opts.twelveHourClock) ? "%I" : "%H";
            var factor;
            var fmt;

            if (opts.timeBase === 'seconds') {
              factor = 1;
            } else if (opts.timeBase === 'microseconds') {
              factor = 1000000
            } else {
              factor = 1000;
            }

            if (t < timeUnitSize.second) {
              var decimals = -Math.floor(Math.log10(t / factor))

              // the two-and-halves require an additional decimal
              if (String(t).indexOf('25') > -1) {
                decimals++;
              }

              fmt = "%S.%" + decimals + "s";
            } else if (t < timeUnitSize.minute) {
              fmt = hourCode + ":%M:%S" + suffix;
            } else if (t < timeUnitSize.day) {
              if (span < 2 * timeUnitSize.day) {
                fmt = hourCode + ":%M" + suffix;
              } else {
                fmt = "%b %d " + hourCode + ":%M" + suffix;
              }
            } else if (t < timeUnitSize.month) {
              fmt = "%b %d";
            } else if ((useQuarters && t < timeUnitSize.quarter) ||
              (!useQuarters && t < timeUnitSize.year)) {
              if (span < timeUnitSize.year) {
                fmt = "%b";
              } else {
                fmt = "%b %Y";
              }
            } else if (useQuarters && t < timeUnitSize.year) {
              if (span < timeUnitSize.year) {
                fmt = "Q%q";
              } else {
                fmt = "Q%q %Y";
              }
            } else {
              fmt = "%Y";
            }

            var rt = formatDate(d, fmt, opts.monthNames, opts.dayNames);

            return rt;
          };
        }
      });
    });
  }

  $.plot.plugins.push({
    init: init,
    options: options,
    name: 'time',
    version: '1.0'
  });

  // Time-axis support used to be in Flot core, which exposed the
  // formatDate function on the plot object.  Various plugins depend
  // on the function, so we need to re-expose it here.

  $.plot.formatDate = formatDate;
  $.plot.dateGenerator = dateGenerator;
  $.plot.dateTickGenerator = dateTickGenerator;
  $.plot.makeUtcWrapper = makeUtcWrapper;
})(jQuery);
